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Race and mental traits: Nicholas Wade’s third error

July 8th, 2014, 11:41pm by Sam Wang

An octogenarian once invited me to his old, exclusive East Coast club to give a talk about neuroscience, my area of specialty. Afterwards, as we walked past oil portraits of old white men across the centuries, the octogenarian pulled me aside, lowered his voice and asked, “I was wondering if you could explain something. What is it about the brains of Chinese and Jews? They seem superior.” Evidently, as a member of one of those tribes (the former), he thought I might know the answer.

In May, the British science journalist Nicholas Wade published “A Troublesome Inheritance,” a book that, at its worst, reminds me of the octogenarian’s question. Throughout “A Troublesome Inheritance,” Wade argues that genetic inheritance, at the level of nations and races, has been shaped by local survival requirements with results that, in turn, shape the cultures in which we live. His interpretation of the genetic and evolutionary evidence has already been roundly criticized. As it turns out, his developmental biology has a few problems as well.

On the surface, his argument sounds a lot like past, discredited claims about the innate superiority of certain races over others. Wade, for his part, says he will have no truck with racism. “Racism and discrimination are wrong as a matter of principle, not of science,” he writes. He says he just wants to tell us the facts. The facts, in the case, are not so much the problem as Wade’s argumentation, which routinely goes much farther than science can justify and weaves a tale that will surely appeal to those who believe that the relative poverty and privilege of different peoples arises from irreparable, inborn differences in their genetic makeup.

First, let’s examine Wade’s many straw men. He argues against the claim that all the people of the world have essentially similar genetic makeup (a position not actually held by any credible geneticists or anthropologists) and argues that races, indeed, are groups delineated from one another by hard biological evidence. To bolster this claim, Wade cites a 2002 landmark study in Science magazine of fifty-two populations from around the world. That study employed a computer program called Structure, which uses differences in DNA to identify distinct groups of humans.

The problem is that Structure* was not intended to be used to prove that any grouping it found was, in fact, biological fact. Indeed, the boundaries between these groupings are so blurry that scientists have to tell the software how many groups to look for. Wade, instead, takes a procrustean approach, focusing on a run of the software that focused on five groups: Europe and central/south Asia; central/south/east Asia; Oceania; Africa; and the Americas. These boundaries roughly match continental geography, but some groups span multiple regions, and the boundaries shift when scientists ask the software for a different number of groups. Rather than running the analysis — which is meant to be agnostic — through a rigorous, scientific process, Wade cherrypicks results that justify his conclusions. What results is a tautology, in which any claims by the computer use Wade’s conclusion as a starting premise.

Worse for Wade’s argument, no matter how finely the software divides up the world population, individual people within a single group differ genetically from one other far more than two groups differ from one other. In the Science magazine study, 94.6% of the variation in genetic content was found within populations, with the remaining 5.4% accounting for differences between groups. Of all the gene variants studied, 93% were found in two or more geographic regions, while 47% were found on every continent. Genetically speaking, very little distinguishes Jews from Japanese, or Nigerians from Armenians.

In the second half of “A Troublesome Inheritance,” Wade completely abandons science for alluring, yet ultimately unsupported speculation. He asserts that (a) different nations reward success in different ways, (b) if success is defined as leaving more offspring, then genetic differences accumulate to make a nation distinctive, and (c) these distinctions shape a nation’s character and prosperity.

It takes breathtaking nerve to make such a chain of unsupported assertions. Wade’s a great storyteller, but to quote geneticist Michael Eisen, “unmoored from data and logic, one can make up an evolutionary explanation for anything.”

Wade asks why the Industrial Revolution took off in England but not in other countries. He asserts that the key difference is an inborn English tendency towards nonviolence and patience, which facilitated productive activities like standing in front of machines for many hours a day. As a biological mechanism, he suggests that the rich left more children on average than the poor, spreading their positive genetic traits downward throughout society. This speculation does not stand up well under scrutiny. The affluent have higher birth rates around the world, not just in jolly old England. And ask any Scotsman about the Highland Clearances of the 19th century. Whatever the cause of the Industrial Revolution’s timing, it is unlikely to have such a simple, genetically determined explanation.

A major problem with this line of speculation is Wade’s mistake of attributing the findings to genetics alone. Change in a nation’s character can occur in remarkably few generations. During the Meiji period from 1868 to 1912, Japan was transformed from a feudal society to one that was ruled by national law. Within a few more generations, Japanese customs became dominated by intense and elaborate courtesies that seem quite far from blood vengeance prevalent during the shogun period. Genetic selection can’t work fast enough to generate such a change. However, social evolution occurs as fast as ideas can move, so it is more logical to say that society changed before their genes could.

Interactions between an individual’s genome and his or her environment can have profound effects on developmental outcomes. In many developed countries, IQ scores have risen by several points per decade, a phenomenon called the Flynn effect. Its discoverer, James R. Flynn, reports that this change has been happening for many decades. For instance, in verbal and performance IQ, an average Danish 14-year-old in 1982 scored 20 points higher than the average person of the same age in his parents’ generation in 1952. The rapidity of the change suggests that some environmental factor, whether educational, nutritional, or other, has had substantial effects on brain development.

The effects of environment on genetic potential are seen most sharply in adoption studies. French children score twelve IQ points higher on average if they are adopted into middle-class homes than if they are adopted into working-class homes. If children are raised in poverty, the gap is as large as eighteen points.

Furthermore, we know that this large difference arises from environmental, not genetic influences. Environment can radically prune back a child’s genetic potential.  For example, the heritability of IQ is nearly eliminated in children who are raised under conditions of poverty. Under these conditions, genes never get the chance to reach their potential. Even if there are genetically based average differences between nations, in individuals they are dwarfed by the effects of environment.

To me, a far more interesting question than the one posed by Wade in “A Troublesome Inheritance” is the question of why such speculations have attracted so much interest. The urge to find genetic roots for differences between ethnic groups is as longstanding as the history of genetics itself. Unsurprisingly enough, “A Troublesome Inheritance” has been endorsed by white supremacist and former Ku Klux Klan grand wizard David Duke, who has said, “the ideas for which I’ve been relentlessly villified are now becoming part of the mainstream because of the irrepressible movement of science and genetics.” It should be noted that Nicholas Wade is not directly responsible for how his work gets spun and coopted, by Duke or by anyone else. Still, Wade’s book seems to needlessly breathe new life racialist thinking of past decades and centuries, while discounting the more exciting, but different directions where the science has gone instead.

As it turns out, Chinese IQs are no different from those of white people. However, I didn’t say this to the octogenarian. I simply told him: “There are all kinds of Chinese people. In fact, some are real layabouts.” He looked incredulous, but I persisted.  ”If you were Chinese you’d know a few of them.”


*Originally, I wrote that STRUCTURE uses the k-means algorithm. Some population geneticists thought that I oversimplified what STRUCTURE does. Different clustering algorithms make different assumptions. STRUCTURE is indeed very similar to k-means, but with a particular error structure – binomial instead of gaussian. This is a fine technical detail compared with the principal point, which is that k is picked by the user, and does not emerge from the data automatically. To learn more, see this Twitter chain and this and this. Thanks to Graham Coop at UC Davis. Also, welcome to readers of Dienekes Pontikos, who has lots to say on this subject.

Tags: Health · Politics

27 Comments so far ↓

  • bks

    Language Log has an interesting takedown of the popular press with regard to its coverage of a paper on genetic contributions to chimp intelligence:

  • Billy

    There is a disturbing trend of racists in science who use “rationalism” to explain differences between groups for something as complicated as intelligence. Before Nicholas Wade, the book “The 10,000 Year Explosion: How Civilization Accelerated Human Evolution” was a prime example of stretching your conclusions too thin. It begins reasonably with lactase persistence, then goes into the deep end for explaining why Jews are inherently superior because of occupational selective pressures.

    The problem with evolutionary biology/psychology/anthropology mixed with genetics is that overreach is too easy and too tempting. When you are dealing with extremely large datasets in genomics, it is easy to get tiny p-values to explain just about any hypothesis you want.

  • Amitabh Lath

    Seriously? Someone is still pushing genetic correlations with IQ in this day and age? Did we not learn from the Charles Murray debacle? Never mind the fact that the concept of IQ as a metric is basically bogus, but one thing that characterizes homo sapiens is *lack* of genetic diversity. We are all uncomfortably closely related.

    This topic is cold fusion. Like cold fusion, proponents believe they can somehow account for environmental effects that are orders of magnitude larger than those they want to study. Because they want so badly to be right, they see signal everywhere.

    PS: I was once asked why Indians were so good at spelling. Until then I had no idea that they (we) were. Even though I was born and brought up in the US, the whole spelling bee craze completely missed my family. For the record, my spelling stinks.

  • Marder

    Also many tropical diseases cause IQ to stay low. Anything that causes anemia is definitely causing big drops in IQ and guess what anemia is rather common in places with brown people. Sickle cell anyone?

    Go check about anemia and IQ. Also don’t forget epigenetics.

  • Marder

    The research they bastardize and misrepresent uses methods that are also not so good. The people who use these methods say so over and over in the studies themselves.

    • Sam Wang

      That is very interesting – see my reply to Paul Allen. However, it’s not as if Wade’s argument would be improved by citing higher-quality, 21st-century evidence…

  • Paul Allen

    Rosenberg’s 2002 study covering 300 microsatellites is a dated, low-resolution study. Modern genome-wide SNP coverage puts the fixation point between 12% and 15%, higher than many putative subspecies of other species.

    Complaining about STRUCTURE, ADMIXTURE, or more neutral approaches like PCA is a losing strategy, because the data does check out. What is actually being measured is another story.

    • Sam Wang

      Thank you, Dr. Smartypants! Are you aware that you are bringing a pipetter to a knife fight?? In seriousness, I am grateful to have smart readers, but um, let’s not miss the point.

      First off, read the book (borrow a copy from an octogenarian friend). Wade goes off on this old study. As a reviewer, so do I. Later work is interesting for its own merits…but we are not talking about those merits! We are discussing whether clustering supports the idea of race at all. Which it does not, 12% or 15% or whatever %. If I were to read 10 years of later work, that would be addressing the wrong question, and giving credence to a point of view that is wrong to start with. The main point is what bks said above – intragroup vs. intergroup comparisons.

      Second…”another story”…well, yes. It’s a great story. A good writer who follows the field (rather than tries to drag the evidence someplace) should write about it! That would not be Nicholas Wade.

      As a working scientist, I am sympathetic to your point. Almost two-thirds of the 67 scientific papers I have co-authored were published since 2002. However, if a layperson asks me about vaccines and autism, or whatever other misconception they might have based on a false reading, I do not need to review later work – I need to dissect why they are wrong.

      Now get off my lawn! ;-)

  • 538 Refugee

    “Wade argues that genetic inheritance, at the level of nations and races, has been shaped by local survival requirements with results that, in turn, shape the cultures in which we live.”

    When I read this I thought it was going to argue that the people at the margins had to be more industrious and creative to survive. Obviously we have these people at the edge of every society so it would be a wash. I guess I’ll have to scrap my notion that natural resources come into play and gladly accept David Duke’s assessment. I don’t have to do anything to be better, I was just born better. Racism, the ultimate refuge of the lazy.

  • Walter

    In short, like Darwin, I put evolution before creationism:

    Many of Wade’s critics, however, put creationism before Darwin.

  • Walter

    Regardless, the “race is a social construct” mantra of Cultural Marxists is mind-numbingly boring and incorrect. These people are the anti-thesis of science. I do hope we’ll be able to move beyond such Marxist propaganda and actually start productively studying human biodiversity.

    • Another Holocene Human

      It’s been studied. There’s very little of it. Phenotype expression doesn’t accurately reflect underlying genetic diversity.

  • Walter

    Points of this are valid, but we must also keep in mind that some of Wade’s critics are advocating outright New Creationism:

    Sorry, but I’m not a creationist.

  • David

    IQ doesn’t measure intelligence, it’s written by middle class people to measure middle class (aka educated) intelligence. The lower IQ’s of twins raised in poor families doesn’t represent lower intelligence. I would wager that the ‘poor’ twins are equally smart in ‘poor’ intelligence (street smarts, for example), except there is no way to measure ‘equal’ here.

    I know that you weren’t asserting this strawman, but I have spent 50 years irritated by the implication that IQ comparisons equal intelligence comparisons. (As a hi-IQ child I knew I was not notably smarter than my playmates, in many ways that mattered.)

    • Dave James

      Knowing that other children are smarter in different ways has to be apparent to these “my genetic research proves what I want to prove” authors. Or at least had to be when they were still children. #disingenuous I hadn’t considered it but your post brought up similar memories of mine. Now that I am thinking of them it is easier to know within myself why I was always suspicious of the prevailing intelligence measuring folks.

  • Karmkshanti Vyapini

    From both the historical and the archeological viewpoint, it is also silly. Human experience is largely about diaspora and resultant interbreeding.

  • bks

    The key idea here is that intragroup differences are greater than intergroup differences. One of the few broadly useful heuristics in biology. –bks

  • Matt McIrvin

    The neo-racialists have been really good at appropriating the rhetoric of skeptic/rationalist argument, and insisting that anyone who disagrees with them is just a denialist bent on ignoring solid science because it’s politically or morally inconvenient. There’s a lot of more-in-sorrow-than-in-anger; a lot of “sorry, I wish for the sake of decency that all races were intellectually equal, but reality is not obliged to cater to our sensibilities.”

    And it’s an effective way to scare off people who are basically liberal and also pride themselves on having evidence-based beliefs, because they’re likely to have the self-questioning impulse to back off and ask “wait a minute, am I just holding this position because it flatters my liberalism?”

    As far as I can tell, the egalitarians actually have the science on their side (though I think there’s something of a split between biologists, whose consensus is more egalitarian, and the psychometricians, who are less so). But the very fact that the result is morally flattering to egalitarians makes it suspect.

  • Wonks Anonymous

    “As it turns out, Chinese IQs are no different from those of white people”
    The numbers I’ve read were typically higher, and the summary in your link doesn’t actually say anything resembling your paraphrase. Instead it says that their achievement is higher than would be expected given their IQ, which is consistent with everything I’ve previously read. Could you provide more accurate numbers for Chinese IQ?

    • Sam Wang

      There isn’t a difference. Perhaps you recall incorrectly. It’s all spelled out in great detail in the Flynn book, which is available at your university’s library. It is true that Asian-American achievement outperforms expectations from IQ, which is an interesting puzzle.

    • Another Holocene Human

      As an American-born Caucasian who went to school with a number of foreign-born East Asians and studied East Asian languages with foreign born teachers, I think there is a difference in middle class cultural expectations between East Asian countries and the US. In the US it’s often felt that talent is everything and if you don’t show an early talent (which should be fostered with intensive after school investments) you’re better off not trying and leaving it to the talented. Whereas East Asians seem to believe that hard work is superior to talent, that having early talent might lead to early failure and it’s better to persist. Americans believe in persistence but more in business and sales (and selling religion) not in educational matters! Americans believe if you fail a class, go a switch to an easier track and focus on what you’re good at. Also, the school systems are set up differently (although the US system has really been in a state of chaos and flux since 2000 and who can say what will happen) in that primary education in the US focused more on method and thinking about problems and problem solving than rote memorization, which East Asian primary schools do a fuck-ton of. But I also feel it’s critical that in the US school gets progressively more difficult each grade through college and then post-graduate study whereas at least in Japan high school is the complete killer (actually, high school entrance exam! so even before, the after school test prep period of junior high) and college is a time to fuck off. I would suspect that since Japanese academics owe a lot to the Chinese system that it’s not that different in China or Taiwan or South Korea for that matter. (Even if the Japanese borrowed the uniforms from Western European schools.)

      A lot of time first gen East Asian students out-perform in public primary schools in the US with a lot of parental support (doing homework after school, etc) and of course if you do well in high school and continue in US colleges and universities you’ll continue to do well because the worst year, freshman year, you’re swimming with thousands of the unprepared, but I’ve seen a lot of rich kids from East Asia who fly over for the first time for college or grad school be totally unprepared for American life or the American university and the kind of thinking, research, skills they expect. Just aside from the language barrier.

  • Bill

    Great piece! Thanks for posting it!

  • Noah Smith

    Awesome, awesome article.

    One thing you didn’t mention that would further chasten the octogenarian: Selective immigration distorts the perceptions of immigrant groups. Most Chinese people who come to America are engineers, scientists, etc. I strongly suspect that there was a big selection effect for Jewish immigrants as well.

  • C.S.Strowbridge

    So much bad science. Too bad this crap will last forever on the internet while real science will be ignored by those who have an agenda.

  • NP

    Nice post, I had not bothered to follow the online debate over this book until I read your post. Seems like the flood of genetic information has given many scientists (and so-called science reporters) the arsenal they needed to support their preconceived notions.

    Since the dawn of population genetics with Fisher, Wright, and Haldane, the role of evolution and genetics in race has been debated by scientists to no productive end. That there are differences between people and races is a given, and recent genomic data clearly support this. But what those data mean beyond that for human behavior and cognition is unknown.

    It is unfortunately easy to color the data with one’s politics and start debates no more sophisticated than those from decades ago. Back then it was the social conservatives and elites who were into eugenics. Nowadays it’s a differently flavored but still eugenics-like thinking along the lines of Wade. Throughout the decades, objective scientists (and most liberal scientists, I’d like to think…) have appreciated the possibility that some data could be argued to support ideas like Wade’s. However, they acknowledge that if one combines the entirety of what we know from both science and real life experience with what we know we do not know from science, it is an untenable interpretation.

    Unfortunately that book seems to have pretty good reviews on Amazon, and some big names (including the WSJ) gave it great praise. Back to 1920 it is…

  • vikram